Determining the Statistical Relationship between the S20 Brittleness Index and Schmidt Hardness of Rocks

Year 2019, Volume: 7 Issue: 4, 839 - 846, 04.12.2019

Hakan Özşen Abdullah Uysal Arif Emre Dursun

https://doi.org/10.36306/konjes.654957

Cited By: 1

Abstract

Determination of the brittleness of rocks is considered as an important preliminary design tool in different mining applications. The brittleness value is an important rock parameter used in the excavation and drilling of rocks. Schmidt's hardness is an inexpensive and easy-to-use surface hardness measure that is commonly used to determine the mechanical properties of rocks, such as strength, cuttability (linear and circular), and permeability. In this study, the S20 brittleness index values were determined by using NTNU model to determine the brittleness values of the rocks which was developed by Blindheim and Bruland (1998). The aim of this study was to investigate the relationship between the S20 brittleness index and Schmidt hardness (RL) values statistically. For this purpose, Schmidt hardness tests and S20 brittleness index tests on 7 different rock samples with different strength properties were performed. Schmidt hardness test values and S20 brittleness index values were statistically evaluated and correlated with SPSS. As a result of this evaluation, it was determined that there was a strong correlation between Schmidt hardness and S20 brittleness index values.

Keywords

S20 brittleness index, Schmidt hardness, statistical estimation, rock mechanics

KAYAÇLARIN S20 KIRILGANLIK İNDEKSİ İLE SCHMIDT SERTLİĞİ ARASINDAKİ İLİŞKİNİN İSTATİSTİKSEL OLARAK BELİRLENMESİ

Abstract

Kayaçların kırılganlığının belirlenmesi farklı madencilik uygulamalarında önemli bir ön tasarım aracı olarak kabul edilmektedir. Kırılganlık değeri kayaçların kazısında ve delinebilirliğinde kullanılan önemli bir kaya parametresidir. Schmidt çekici sertliği ise kayaların dayanım, kesilebilirlik (doğrusal ve dairesel) ve delinebilirlik gibi mekanik özelliklerini belirlemek için yaygın olarak kullanılan ucuz ve kolaylık sağlayan bir yüzey sertliği ölçüsüdür. Bu çalışmada, kayaçların kırılganlık değerlerini belirlemek için Blindheim ve Bruland’ın (1998) geliştirdiği S20 kırılganlık indeksinin NTNU modeli kullanılmıştır. Burada amaç, kayaçların S20 kırılganlık indeksi ile Schmidt sertliği (RL) değerleri arasındaki ilişkinin istatistiksel olarak araştırılarak yeni bir tahmin yöntemi geliştirmesidir. Bunun için, farklı dayanım özelliklerine sahip 7 farklı kayaç numunesi üzerinde S20 kırılganlık indeks deneyi ile Schmidt çekici sertlik deneyleri yapılmıştır. Schmidt çekici sertliği değerleri ile S20 kırılganlık indeksi değerleri “SPSS” programı yardımıyla istatistiksel olarak değerlendirilmiş ve korelasyon yapılmıştır. Bu değerlendirme sonucunda Schmidt çekici sertliği değerleri ile S20 kırılganlık indeksi değerleri arasında yüksek korelasyonlu bir ilişki olduğu belirlenmiştir.

Keywords

S20 kırılganlık indeksi, Schmidt sertliği, istatistiksel tahmin, kaya mekaniği

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